The ability to give, when you have limited resources is much more appreciated, rather than when you have a lot, and you give a little.

Reminds me of the story of a Sahabi. It was before on the battles, the Prophet S.A.W.S. had asked his companions to collect whatever they could. This particular Sahabi ( I don't remember his name) had nothing, so he worked all night at in a Jew's orchard, and in return was given a handful of dates. He took those dates and gave all of them to the Prophet S.A.W.S. Our Holy Prophet S.A.W.S. took those dates, and spread them over the items that had been collected, and said " These dates, are worth more then everything collected here." Just because of the sincerity of that Sahabi's actions. May Allah forgive me if I left something out.
@Zarvan could shed more light on this incident

Moral of the story: Sometimes, even a small action done with sincerity and piety can mean a lot!